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  1. Core Server
  2. SERVER-18966

Allow exclusion in $project stage of aggregation pipeline

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Details

    • Minor Change
    • Query 11 (03/14/16), Query 12 (04/04/16), Query 13 (04/22/16), Query 14 (05/13/16), Query 15 (06/03/16), Query 16 (06/24/16)

    Description

      There is currently no way to easily specify that project stage keep all fields except for a particular one (with exception of _id).

      This can be helpful to limit the amount of data returned when some aggregation also needs to be done.

      Examples

      // Exclude a single field.
      		 
      > db.example.insert([
      		 
        {_id: 0, a: 1}
      		 
      ]);
      		 
      > db.example.aggregate([{$project: {a: 0}}])
      		 
      {_id: 0}
      		 
      > db.example.aggregate([{$project: {a: false}}])  // Means the same thing as above.
      		 
      {_id: 0}
      		 
       
      		 
      // Exclude a nested field.
      		 
      > db.example.drop()
      		 
      > db.example.insert([
      		 
        {_id: 0, a: {b: 1, c: 1}}
      		 
      ]);
      		 
      > db.example.aggregate([{$project: {'a.b': 0}}])
      		 
      {_id: 0, a: {c: 1}}
      		 
      > db.example.aggregate([{$project: {a: {b: 0}}}])  // Means the same thing as above.
      		 
      {_id: 0, a: {c: 1}}
      		 
       
      		 
      // Exclude a nested field from an array.
      		 
      > db.example.drop()
      		 
      > db.example.insert([
      		 
        {_id: 0, a: [{b: 1, c: 1}, {b: 2, c: 2}]}
      		 
      ]);
      		 
      > db.example.aggregate([{$project: {'a.b': 0}}])
      		 
      {_id: 0, a: [{c: 1}, {c: 2}]}
      		 
      > db.example.aggregate([{$project: {a: {b: 0}}}])  // Means the same thing as above.
      		 
      {_id: 0, a: [{c: 1}, {c: 2}]}

      Attachments

        Issue Links

          duplicates

          New Feature - A new feature of the product, which has yet to be developed. SERVER-22787 Add $lookup.excludeLocalField to exclude local field from output

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Backlog
          is depended on by

          New Feature - A new feature of the product, which has yet to be developed. SERVER-22436 Allow parsing of string literals in aggregation's $project

          • Major - P3 - Major loss of function.
          • Closed
          is documented by

          Task - A task that needs to be done. DOCS-8973 Allow exclusion in $project stage of aggregation pipeline

          • Major - P3 - Major loss of function.
          • Closed
          is duplicated by

          Bug - A problem which impairs or prevents the functions of the product. SERVER-23411 Inconsistent results when setting a nested field in $project

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. SERVER-22436 Allow parsing of string literals in aggregation's $project

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-30633 Large performance regression for large aggregation queries

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. DRIVERS-297 Aggregation Framework Support for 3.4

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. SERVER-24921 No way to $project out just the _id field in aggregation

          • Major - P3 - Major loss of function.
          • Closed
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-6714 Array in input doc schema incorrectly affects $project output

          • Major - P3 - Major loss of function.
          • Closed

          Bug - A problem which impairs or prevents the functions of the product. SERVER-23411 Inconsistent results when setting a nested field in $project

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. CSHARP-1598 allow exclusion in $project stage

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. JAVA-2148 Ensure proper builder support for exclusions in the $project stage of an aggregation pipeline

          • Major - P3 - Major loss of function.
          • Closed

          New Feature - A new feature of the product, which has yet to be developed. SERVER-5781 Implement $addFields aggregation stage for using expression language to add new fields to a document

          • Major - P3 - Major loss of function.
          • Closed

          Activity

            People

              charlie.swanson@mongodb.com Charlie Swanson
              asya.kamsky@mongodb.com Asya Kamsky
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              Dates

                Created:
                Updated:
                Resolved: